Modem air traffic control systems are built in conformance to rigid software development standards where safety and reliability are the key design drivers. At the same time the demand for accessible operational data through access to the system is an another requirement. Meeting these two divergent requirements require unique and novel solutions.
One design feature that system providers have endeavored to build into modem air traffic control systems is the ability to record every system or user action and store this data into a database. This feature leads to greater reliability in that system or user errors can be captured and analyzed and the system modified to prevent such errors from occurring. As well, there is usually commercial value in such data in that it provides a direct record of traffic movements and can be used for extracting statistics, billing data, or be used for training purposes. Timely access to this data is therefore necessary for both business and safety purposes.
In order both enhance both the perception and actual security, air traffic control systems usually are isolated from connectivity with outside systems. Physical access is usually very strictly controlled through secure login procedures in locked or carded facilities where actions are both monitored and audited.
The problem that the system is attempting to solve is that the system security requirements are in direct conflict with the access requirements; both of which appear to be quite valid.
Historically the operational data transfer has been completed by manual means requiring lengthy and error prone procedures. The manual method has limitations in that it is usually not performed in a frequent or timely manner nor can it handle large amounts of data. A design that would permit secure, safe data transfer without human intervention on a timed basis that was robust and secure is a crucial requirement in the unique area of the design of air traffic control systems.